All of leiz's Comments + Replies

leiz30

OK I agree that the word 'inevitably' is ambiguous. Regardless of the accuracy of the literal-to-logical translations, I think the reason the logical expression of the statement of the article does not match that of the final conclusion, as your logical reasoning proves, is that the writer were not doing the very logical reasoning but doing medical research and thus proposing something new, not something of equivalent logical consequences.

Their first statement:

This study tested and rejected the hypothesis that artificial food coloring causes hyperactiv

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leiz10

I think that the universal quantifier in

!( ∀child ( eats(child, coloring) ⇨ hyperactive(child) ) )

is not appropriate.

The original statement

artificial food coloring causes hyperactivity in all children.

only implicates that artificial food coloring was responsible for all children's hyperactivity, not that children who ever ate artificial food coloring would inevitably have hyperactivity. So the formula without universal quantifier is more reasonable and thus the final statement of the article is without problem.

-3PhilGoetz
No, you are picking up on the lack of details about time that I mentioned. You really don't want me to write a proposition incorporating the time relationship between when cookies were eaten and when and how behavior was measured. The formula without a quantifier wouldn't even be well-formed. It would have no meaning.